488 resultados para Ctenocephalides felis felis


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BACKGROUND & AIMS: Infection with Helicobacter induces a T helper type 1 response in mice and humans. Mice can be cured or protected from infection with Helicobacter by mucosal immunization with recombinant H. pylori urease B subunit (rUreB). This study characterizes the immune response of infected mice immunized with rUreB. METHODS: BALB/c mice were infected with H. felis. Two weeks later, they were orally immunized four times with rUreB and cholera toxin (CT) at weekly intervals. Controls were only infected or sham-immunized with CT. Animals were killed at various times after immunization. Splenic CD4(+) cells were obtained and cultured in vitro with rUreB to evaluate antigen-specific proliferation and induction of interferon gamma and interleukin 4 secretion. RESULTS: All rUreB-immunized mice (n = 8) were cured from infection 3 weeks after the fourth immunization. Immunization induced a proliferative response of splenic CD4(+) cells, a progressive decrease in interferon gamma secretion, and a concomitant increase in interleukin 4 secretion after each immunization. A simultaneous increase in rUreB specific serum immunoglobulin G1 levels was observed in infected/immunized mice. CONCLUSIONS: In BALB/c mice, therapeutic mucosal immunization with rUreB induces progressively a Th2 CD4(+) T cell response resulting in the elimination of the pathogen.

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This article summarizes the basic principles of Fourier Transform Infrared Spectroscopy, with examples of methodologies and applications to different field sciences.

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Corneal samples of cats with and without corneal diseases were screened with a pan-Chlamydiales PCR and specific PCRs for Parachlamydia, Protochlamydia, Chlamydophila felis, Acanthamoeba and feline herpesviruses (FHV-1). Several corneal samples tested positive for Parachlamydia and related Chlamydiales, indicating cat exposure to these intracellular bacteria.

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Colorectal cancers exhibit a high telomerase activity, usually correlated with the hypermethylation of the promoter of its hTERT catalytic subunit. Although telomerase is not expressed in normal tissue, certain proliferative somatic cells such as intestinal crypt cells have demonstrated telomerase activity. The aim of this study was to determine whether a correlation exists between telomerase activity, levels of hTERT methylation and telomere length in tumoral and normal colorectal tissues. Tumor, transitional and normal tissues were obtained from 11 patients with a colorectal cancer. After bisulfite modification of genomic DNA, hTERT promoter methylation was analyzed by methylation-sensitive single-strand conformation analysis (MS-SSCA). Telomerase activity and telomere length were measured by a fluorescent-telomeric repeat amplification protocol assay and by Southern blotting, respectively. A significant increase of hTERT methylation and telomerase activity, and a reduction of the mean telomere length were observed in the tumor tissues compared to the transitional and normal mucosa. In the transitional and normal mucosa, telomerase activity was significantly lower than that in tumor tissues, even with high levels of hTERT methylation. Nevertheless, hTERT promoter methylation was not linearly correlated to telomerase activity. These data indicate that hTERT promoter methylation is a necessary event for hTERT expression, as is telomerase activity. However, methylation is not sufficient for hTERT activation, particularly in normal colorectal cells.

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Background To examine the effect of anastomosis on experimental carcinogenesis in the colon of rats. Methods Forty-three 10-week-old male and female Sprague-Dawley rats were operated on by performing an end-to-side ileorectostomy. Group A:16 rats received no treatment. Group B: 27 rats received 18 subcutaneous injections weekly at a dose of 21 mg/kg wt of 1–2 dimethylhydrazine (DMH), from the eighth day after the intervention. Animals were sacrificed between 25–27 weeks. The number of tumours, their localization, size and microscopic characteristics were recorded. A paired chi-squared analysis was performed comparing tumoral induction in the perianastomotic zone with the rest of colon with faeces. Results No tumours appeared in the dimethylhydrazine-free group. The percentage tumoral area was greater in the perianastomotic zone compared to tumours which had developed in the rest of colon with faeces (p = 0.014). Conclusion We found a cocarcinogenic effect due to the creation of an anastomosis, when using an experimental model of colonic carcinogenesis induced by DMH in rats.

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The aim of the present experiment was to investigate the effect of corticosteroids (exogen) on in vitro testosterone secretion after stress by transportation (40 minutes). Feline testes (Felis silvestris catus) were incubated in the following media: TCM 199; TCM 199 + hCG 10_7M; TCM 199 + hydrocortisone 10_7M, or TCM 199 + hCG + hydrocortisone. The animals (n=21) were allocated into three groups: (S) that arrived at 3 h prior to surgery, (A) that remained in the laboratory for 36 h before being submitted to surgical procedure, and (C) that were also allowed to remain for 36 hours in the laboratory before the surgical procedure, but whose testes had been incubated with hydrocortisone prior to incubation in the referred media. The results showed that group S secreted higher levels of testosterone, regardless of the culture media. It is noteworthy that the suppressing action of hydrocortisone sodium succinate led to a reduction in the testosterone concentration, despite the presence of hCG.

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Capybaras (Hydrochaeris hydrochaeris) are among the main hosts of Amblyomma spp. ticks, which is able to transmit Rickettsia species to human beings and animals. Since they are often infested with potential vector ticks, capybaras may be used as sentinels for rickettsiosis, such as the Brazilian Spotted Fever. The aim of the present study was to determine the prevalence of antibodies against Rickettsia spp. using the indirect immunofluorescence assay (IFA) in 21 free-ranging and 10 captive animals from the Zoological Park of the 'Bela Vista Biological Sanctuary' (BVBS), Itaipu Binational, Foz do Iguaçu, Southern Brazil. Antigens of six rickettsial species already identified in Brazil (Rickettsia rickettsii, R. parkeri, R. bellii, R. rhipicephali, R. amblyommii and R. felis) were used for IFA. Ticks from each capybara were collected for posterior taxonomic identification. A total of 19 (61.3%) samples reacted to at least one of tested species. Seropositivity was found in 14 (45.2%), 12 (38.7%), 5 (16.1%), 4 (12.9%), 3 (9.7%) and 3 (9.7%) animals for R. rickettsii, R. bellii, R. parkeri, R. amblyommii, R. felis and R. rhipicephali, respectively. Two captive capybaras presented suggestive titers of R. rickettsii infection and one sample showed homologous reaction to R. parkeri. Only one free-ranging capybara presented evidence R. bellii infection. Ticks collected on capybaras were identified as Amblyomma dubitatum e Amblyomma sp. Results evidenced the rickettsial circulation in the area, suggesting a potential role of capybaras on bacterial life cycle.

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Eight Panthera onca (Po), 13 Felis concolor (Fc), 7 Felis yagouaroundi (Fy), 7 Felis tigrina (Ft) and 5 Felis pardalis (Fp) specimens from São Paulo State zoos were used. All animals were restrained with darts containing 10 mg/kg ketamine and 1 mg/kg xylazine. Venous blood samples were collected as soon as possible (within 15-20 min) and serum was frozen until the time for cortisol quantification. Cortisol was determined using a solid phase radioimmunoassay with an intra-assay coefficient of 8.51%. Data were analyzed statistically by the Kruskal-Wallis test, followed by Dunn's multiple comparisons test, and the one-sample t-test, with the level of significance set at P<0.05. Data are reported as means ± SEM. Cortisol levels differed among the captive felines: Po = 166 ± 33a, Fc = 670 ± 118b, Fy = 480 ± 83b, Ft = 237 ± 42ab, Fp = 97 ± 12a nmol/l (values followed by different superscript letters were significantly different (P<0.001)). Since most of the veterinary procedures on these species involve chemical restraint, these results show the necessity of preventive measures in order to minimize the effect of restraint stress on more susceptible species

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Conocer la situación laboral y profesional de los titulados universitarios que finalizaron sus estudios en las promociones 85/86, 86/87 y 87/88 en las universidades de la Comunidad Valenciana. Planteamiento de hipótesis. El trabajo de campo se realiza en tres etapas: 1. Obtención de una relación nominal de los titulados, a fin de estimar el volumen de los datos a manejar. 2. Selección aleatoria de los mismos para obtener una muestra representativa de la población a la que remitir los cuestionarios. 3. Control de los cuestionarios recibidos y codificación de los mismos, agrupando las treinta titulaciones estudiadas en cuatro grupos: Ciencias Humanas y Sociales, Ciencias Básicas, Ciencias de la Salud y Ciencias Tecnológicas. Análisis de los resultados. Test de chi-square. Tablas. Los índices de desempleo de los titulados universitarios, aunque inferiores a los del conjunto de la población, son significativos, siendo el colectivo de mujeres el más discriminado. Las titulaciones que otorgan mayor facilidad para acceder al mercado de trabajo son las tecnológicas. Existe una mayor tasa de desempleo para las titulaciones de ciclo corto que para las licenciaturas. Más de la mitad de los titulados trabajan en el sector público, y en especial el colectivo de mujeres. La mayoría de los titulados ocupados poseen un empleo relacionado con los estudios cursados, y ven reconocida su titulación a la hora de formalizar un contrato.

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Capsule Avian predators are principally responsible. Aims To document the fate of Spotted Flycatcher nests and to identify the species responsible for nest predation. Methods During 2005-06, purpose-built, remote, digital nest-cameras were deployed at 65 out of 141 Spotted Flycatcher nests monitored in two study areas, one in south Devon and the second on the border of Bedfordshire and Cambridgeshire. Results Of the 141 nests monitored, 90 were successful (non-camera nests, 49 out of 76 successful, camera nests, 41 out of 65). Fate was determined for 63 of the 65 nests monitored by camera, with 20 predation events documented, all of which occurred during daylight hours. Avian predators carried out 17 of the 20 predations, with the principal nest predator identified as Eurasian Jay Garrulus glandarius. The only mammal recorded predating nests was the Domestic Cat Felis catus, the study therefore providing no evidence that Grey Squirrels Sciurus carolinensis are an important predator of Spotted Flycatcher nests. There was no evidence of differences in nest survival rates at nests with and without cameras. Nest remains following predation events gave little clue as to the identity of the predator species responsible. Conclusions Nest-cameras can be useful tools in the identification of nest predators, and may be deployed with no subsequent effect on nest survival. The majority of predation of Spotted Flycatcher nests in this study was by avian predators, principally the Jay. There was little evidence of predation by mammalian predators. Identification of specific nest predators enhances studies of breeding productivity and predation risk.

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The purpose of this study was to conduct a habitat suitability analysis of the critically endangered Florida panther (Felis concolor coryi) in Florida. We gathered land cover, population and road data from the Florida Geographic Data Library and performed map algebra using ESRI’s ArcGIS to compile a suitable habitat map. We found that there is 20381.7 km² of highly suitable habitat and 557124.4 km² of less desirable but usable habitat for the Florida panther. The highest concentration of highly suitable habitat is in Big Cypress National Park, with smaller patches in Tates Hell State Forest and along the southeast portion of the Panhandle. Due to extensive fragmentation, however, and without establishment of habitat linkages to the existing southern population, there is little chance of survival of additional panther populations in much of northern Florida.

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Leishmaniasis are endemic diseases wild spread in the New and Old World, caused by the flagelated protozoan Leishmania. In the New World, the distribution of different forms of leishmaniasis is mostly in tropical regions. In the State of Rio Grande do Norte, Northeast Brazil, 85% of the captured sand flies fauna is Lutzomyia longipalpis. The distribution of the sand fly vector in the state overlaps with the disease distribution, where the presence of sand flies is associated with presence of animals shelters. The aim of this study was to analyse the blood meal preference of sand flies vector from the genus Lutzomyia spp. in laboratory conditions, to verify the vector life cicle at different temperatures sets and to identify the main blood meal source in endemic areas for visceral leishmaniasis (VL) at peri-urban regions of Natal. Sand flies samples were collected from the municipalities of São Gonçalo do Amarante and Nísia Floresta where female sand flies were grouped for the colony maintenance in the laboratory and for the analysis of the preferred source of sand fly blood meal in natural environment. The prevalence of blood meal preference and oviposition for the females sand flies was 97% for Cavia porcellus with oviposition of 19 eggs/female; 97% for Eqqus caballus with 19 eggs/female; 98% for human blood with 14 eggs/female; 71.3% for Didelphis albiventris with 8.4 eggs/female; 73% for Gallus gallus with 14 eggs/female; 86% for Canis familiaris with 10.3 eggs/female; 81.4% for Galea spixii with 26 eggs/female; 36% for Callithrix jachus with 15 eggs/female; 42.8% for Monodelphis domestica with 0% of oviposition. Female sand flies did not take a blood meal from Felis catus. Sand flies life cycle ranged from 32-40 days, with 21-50 oviposition rates approximately. This study also showed that at 32°C the life cycle had 31 days, at 28° C it had 50 days and at 22°C it increased to 79 days. Adjusting the temperature to 35°C the eggs did not hatch, thus blocking the life cycle. A total of 1540 sand flies were captured, among them, 1.310 were male and 230 were female. Whereas 86% of the sand flies captured were Lu. longipalpis as compared to 10.5% for Lu. evandroi and, 3.2% for L. lenti and 0.3% for Lu whitmani. The ratio between female and male sandfly was approximately 6 males to 1 female. In Nísia Floresta, 50.7% of the collected females took their blood meal from armadillo, 12.8% from human. Among the female sand flies captured in São Gonçalo do Amarante, 80 of them were tested for the Leishmania KDNA infectivity where 5% of them were infected with Leishmania chagasi. Female Lutzomyia spp. showed to have an opportunistic blood meal characteristic. The behavioral parameters seem to have a higher influence in the oviposition when compared to the level of total proteins detected in the host s bloodstream. A higher Lu. longipalpis life cycle viability was observed at 28°C. The increase of temperature dropped the life cycle time, which means that the life cycle is modified by temperature range, source of blood meal and humidity. Lu longipalpis was the most specie found in the inner and peridomiciliar environment. In Nísia Floresta, armadillos were the main source of blood meal for Lutzomyia spp. At São Gonçalo do Amarante, humans were the main source of blood meal due to CDC nets placed inside their houses

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)